The radiation exposure resulting from medical imaging has become a public safety concern. Dose reduction for pediatric patients is particularly important since such patients are at increased risk owing to the enhanced radiosensitivity of their tissues and the longer time-period over which stochastic radiation effects may manifest. The objective of this proposal is to develop and validate techniques that can be used to minimize the radiation exposure to pediatric patients undergoing molecular imaging procedures without adversely impacting the diagnostic quality of the images. The hypothesis of this proposal is that it is possible to reduce the absorbed dose received by pediatric molecular imaging patients without compromising the image quality of the study by: (1) individualizing the amount of administered activity and the image acquisition time to better account for the effects that patient-specific body size and shape may have on the detector count-rate density; (2) adjusting acquisition parameters to account for the smaller field of view in pediatric imaging; (3) improving image reconstruction methods to enable image generation from these lower-count, smaller field-of-view images. In current clinical practice, dosing for pediatric molecular imaging has focused on rule-of-thumb approaches to identifying the activity administered to children for different imaging procedures. By using state-of-the-art simulation, image quality evaluation and radiation dosimetry tools, the work proposed in this grant application will examine dose reduction methods in a much more rigorous and, scientifically validated manner. This approach will lead to clinically implementable dose reduction techniques for pediatric (and potentially adult) molecular imaging on par with national efforts to reduce doses in pediatric and adult CT and fluoroscopically guided interventions without adversely impacting the diagnostic quality of the images. PUBLIC HEALTH RELEVANCE: The radiation exposure resulting from medical imaging has become a public safety concern. The objective of this proposal is to develop and validate techniques that can be used to reduce the radiation exposure to pediatric patients undergoing molecular imaging procedures using methods that retain the diagnostic quality of the images.